class Solution {
public:
    vector<int> searchRange(vector<int>& nums, int target) {
        if (nums.empty())
            return {-1, -1};
        // 找左端点
        int left = 0, right = nums.size() - 1;
        while (left < right) {
            int mid = left + (right - left) / 2;
            if (nums[mid] < target) {
                left = mid + 1;
            } else {
                right = mid;
            }
        }
        vector<int> v;
        if (nums[left] != target) {
            return {-1, -1};
        } else {
            v.push_back(left);
        }
        // 找右端点
        left = 0, right = nums.size() - 1;
        while (left < right) {
            int mid = left + (right - left + 1) / 2;
            if (nums[mid] > target) {
                right = mid - 1;
            } else {
                left = mid;
            }
        }
        if (nums[left] != target) {
            return {-1, -1};
        } else {
            v.push_back(left);
        }
        return v;
    }
    };